Programmed Death Ligand-1 (PD-L1) Expression in the Programmed Death Receptor-1 (PD-1)/PD-L1 Blockade: A Key Player Against Various Cancers.

Context: - Immune checkpoint pathways, including programmed death receptor-1/programmed death ligand-1 (PD-1/PD-L1) signaling pathway, which are important in mediating self-tolerance and controlling self-damage, can sometimes be manipulated by cancer cells to evade immune surveillance. Recent clinical trials further demonstrate the efficacy of PD-1/PD-L1-targeted therapy in various cancers and reveal a new era of cancer immunotherapy.

Objective: - To review the mechanism of the PD-1/PD-L1 signaling pathway, the regulation of this pathway, PD-1/PD-L1 as a predictive and/or prognostic marker in various cancers, and strategies of measuring PD-L1 expression.

Detection of BRAF mutation in the cytocentrifugation supernatant fluid from fine-needle aspiration of thyroid lesions may enhance the diagnostic yield.

Objective: BRAF mutations using cellular DNA from fine-needle aspiration (FNA) specimens are commonly used to support the diagnosis of papillary thyroid carcinoma (PTC). The goal of this study was to preliminarily evaluate the diagnostic utility of detecting BRAF mutations in the routinely discarded FNA specimen supernatant fluid.

Materials And Methods: Seventy-eight FNAs of thyroid lesions were evaluated for BRAF mutations using both cellular and supernatant DNA.